Example: If your Content Page is about airlines, but doesn't include the word aviation, you could add this word. A popular practice is adding keywords that contain competitors names so your content appears and is indexed also when those keywords are used.

Meta description allows you to customize what is shown as a description when your Content comes up in search results on search engines and in social media. You may want to add a brief 2 sentences that sums up your content that may not appear on the page itself.